JPS58222966A - Fuel oil feeder for internal-combustion engine - Google Patents

Abstract

PURPOSE:To prevent a flush of returned fuel oil out of an engine from occurring inside an air separator as well as to promote the recovery of heat energy, by installing a cooling device for the returned fuel oil in a returned fuel oil passage leading the oil from the engine into the air separator. CONSTITUTION:High temperature, returned fuel oil from a Diesel main engine 5 enters an air separator 6 after being cooled to the extent of below 100 deg.C in a cooling coil 12 installed inside a fuel oil service tank 1, which is kept relatively low in temperature, on the midway in a fuel oil return pipe 9. On the other hand, oil inside the fuel oil service tank 1 is heated by the returned fuel oil. Therefore, as the heated oil enters the air separator after its temperature cooled up to below 100 deg.C, there is no fear of any flush of water, etc., and also no spillover of a portion for oil from the air separator will happen. Moreover, since the fuel oil inside the service tank 1 is used as a cooling medium, heat loss due to cooling will in no case occur at all.

Description

[Detailed description of the invention] The present invention relates to an improvement in a fuel supply system for an internal combustion engine.

FIG. 1 is an explanatory diagram schematically showing a fuel supply system for a large marine diesel main engine that uses low quality oil that requires heating for combustion. In the figure, 1 is a fuel service tank;
2 is a flow meter, 3 is a fuel booster pump, 4 is a fuel heater, 5 is a diesel main engine, 6 is an air separator, 10 is an air vent pipe of the air separator 6, and 11 is a drain pipe. 7 and 8 are fuel supply pipes from the fuel service tank 1 to the diesel main engine 5; 9 is a return fuel pipe for returning excess fuel;
It is connected to the suction side of the fuel intake pump 3 via an air separator 6.

/ Due to the deterioration of fuel quality, the heating temperature of fuel has been increased to 130-150℃
With the above equipment, when the return oil enters the air separator (atmospheric pressure type), water and evaporated components in the fuel are removed. Flash.

It has become common to see problems in which oil, flashed oil, and moisture leak out of the air separator and reactor along with the separated air.

/ (a) The capacity of the air separator to prevent leakage.

It is effective to have sufficient height and (b) to suppress the flash of return oil by making the air vent pipe sufficiently high, but these are difficult to achieve in the limited ship engine room. There are many.

For this reason, there is a concern about fuel scattering accidents from the air vent pipe, and if a seamount drain pipe such as No. 11 is installed,
Mushi oil enters fuel service tank 1, 6fC1la total 2
reading does not accurately indicate diesel main engine consumption.

An object of the present invention is to provide a fuel supply device for an internal combustion engine that eliminates the above-mentioned drawbacks, and has two characteristics.
Airse the return fuel from the engine! A cooling device is provided in the return fuel path leading to the rotor to cool the return fuel by the fuel supplied to the engine.

In this case, the return fuel can be cooled before entering the air separator to prevent flanone formation of the return fuel in the air separator, and the fuel supplied to the engine can be used as a cooling medium to recover thermal energy. .

The present invention can be widely applied to internal combustion engines that use low-quality oil as fuel that requires heating.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an explanatory diagram showing one embodiment of the apparatus according to the present invention.

In the figure, 1 is a fuel service tank, 2 is a flow meter, and 3 is a fuel service tank.
is the fuel booster pump 0 and 4 are the fuel heaters.

5 is the diesel main engine, and 6 is the air aerator.

10 is an air vent pipe of the air separator 6, 1 ] (r
i, Tren pipes 7 and 8 are fuel supply pipes from the fuel service tank 1 to the diesel main engine 5; 9 is a return fuel pipe for returning excess fuel; it is connected to the suction side of the fuel booster pump 03 via the air storage/9 regulator 6; be done.

Reference numeral 12 denotes a return fuel cooling coil, which is installed below the lowest oil level 1a in the fuel service tank 1.

” The effect in the case of the second configuration will be described.

The high temperature return fuel from the main diesel engine 5 is.

In the middle of the return fuel pipe 9, the temperature is relatively low (usually 50 to 80°C).
) The fuel enters the air separator 6 after being cooled down to below 100° C. in the cooling coil 12 installed in the fuel service tank 1 . On the other hand, the oil in the fuel service tank 1 is heated by the return fuel 1゛□ oil.

The above case has the following effects.

Since the returned fuel enters the air separator after its temperature has been cooled to below 100° C., there is no risk of moisture flashing, and therefore no oil will come out from the air separator or router.

Since the fuel in the fuel service tank is used for cooling, no heat loss occurs due to cooling.

FIG. 3 is an explanatory diagram showing another embodiment of the apparatus according to the present invention.

In this case, an ordinary heat exchanger 13 is used for cooling the return fuel, and the other aspects are the same as the embodiment shown in FIG. 2 described above. Its operation and effect are also the same as in the previous embodiment.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a conventional fuel supply device, and FIG. 2 is an explanatory diagram showing an embodiment of the device according to the present invention. FIG. 3 is an explanatory diagram showing another embodiment of the apparatus according to the present invention. ■...Fuel service tank, 5...Diesel main engine, 6...Air separator, 9...Return fuel pipe, t
2... Return fuel cooling coil, 13... Heat exchanger. 1.5 bald (7159) Patent attorney Isoyama, Ehiki1゛)1stopzol゛1・2iρ

Claims (1)

[Claims] 1. A fuel supply device for an internal combustion engine, characterized in that a cooling device is provided in a return fuel path that introduces return fuel from the engine into an air separator, for cooling the return fuel with fuel supplied to the engine.